The midland journal. (Rising Sun, Md.) 1885-1947, 1887-07-15
Ladies' Department.
RE Housekeoper as Chemist.

that every chemist ought to be
good cook, the operations in those
two widely separated occupations
being so similar. It is true that the
processes of evaporation, distillation
desiccation, ect., have strong re-
semblance to those carried on by the
presiding genius of the kitchen; and
conversely, the housekeeper, in her
every day work, avails herself I'M
consciously of many important sci
entific principles.
The substances used as food be-
long mainly to the class of organic
bodies. They are composed princi-
pally of carbon, hydrogen, oxygen
and nitrogen, and are of very com.
pick constitution. The action Of
heat upon them is often to change
their character very decidedly and
yet In many cases the chemist can
not perceive any difference in their
composition. Take the case Of al
bumen, for instance, which forms the
white Of an egg, and is also present
in meats of all kinds. Upon heating
to I63 degrees, the watery liquid be-
comes changed into tough, white
solid, more or less difficult of diges-
ton; but the change appears to be
only physical one, and the chemi-
cal composition remains the same.
This property of coagulation is made
use of in clearing coffee from its sed-
iment. When the liquid white of an
egg is stirred into boiling coffee, it
solidifes at once, enclosing in the
mass all the particles held in snspen-
sion and leaving the liquid beauti-
fully clear. The skin is similar, on
ly in this case the gelatine of the
skin unites with the tannin of the
coffee to form leathery substance,
which acts like coagulated albumen.
Gelatine i, made from the bones
and tissues OF animals, and is of con-
siderable Importance in the domes-
tic economy. In its coarser forms it
is known as glue, but when properly
refined forms the bright, clear, cook
ing gelatine. Its most characteristic
property is that Of gelatinization.
1t is Unsuitable in cold water, but alb
serbs it. swelling up and becoming
soft. Upon heating the water, it
rapidly dissolves; and upon cooling
again; after while sets into more
or less firm mass known as jelly.
Prolonged boiling of the solution
causes it to lose this property, as
housewives frequently discover to
their sorrow when the jelly absolute
refuses to sicily" The addition of
a small quantity of strong acid, like
nitric, also destroys this property,
without injuring it's adhesive qualit-
les; and the familiar prepared liquid
glue'' is made in this way. Fruits
contain body known as pectine,
which also possesses the property of
gelatinizing although its composition
is very different from true gelatine,
which is found only in animal or.
ganisms. The stimulating effects of
coffee and tea are due to an alkaloid
known as caffeine or theme, accord
ing to the source from which it was
obtained. Its composition is the
same in both cases and the pure al
kaloid is frequently used in medi-,
cine, The agreeable flavor of these
beverages is due to various aromatic
substances which are extracted by
the boiling water from the leaf or
berry; but the restoring and exhiler-
ating effects must be credited to the
alkaloid, which seem to bear some
resemblance to the we'll known CO.
caine.
Flour is one of the most indispen-
sable articles used in the family. 1t
consists principally of starch, with
more or less gluten and inorgantic
or mineral constituents, according to
its coarseness or fineness. Some Of
the finest bolted flours consist almost
entirely of pure starch. and are in
ferior in nutritive value to the coars-
er varieties; although they make
much whittier and much more attrac-
tive loaf of bread, The "ralsing" of
dough Is true process of fermenta-
ton, precisely similar to that of the
brewer or whiskey distiller. The
yeast plant, when mixed with the
flour acts in some mysterious way
upon the starch, first transforming it
into grape sugar, and then breaking
this DIP into alcohol and carbonic acid
gas. The alcohol is partially driven
off by the heat of the oven. though
in freshly baked loaf Its odor is
quite evident; and the carbonic acid
gas permeates the dough, its expan-
sion causing it to puff up, or "rise"
rendering it light and spongy.
Two molecules of starch with tie
addition of molecule of water from
a molecule Of cane sugar, is another
substance in universal use. Unfor-
tunately tbs only in the wonderful
laboratory of the growing plant that
this combination can be effected, or
the price of sugar would be even
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